Stem twining, covered with spreading hairs. Leaves herbaceous; petiole 5–15 lin. long, pubescent with spreading hairs; blade 2–3 1/2 in. long, 3/4–2 1/4 in. broad, cordate-ovate or ovate-lanceolate, acuminate, cordate at the base, softly pubescent on both sides. Cymes umbel-like, 12–20-flowered; peduncles 3–6 lin. long, pubescent with spreading hairs; bracts 1 1/2–3 lin. long, narrowly lanceolate or subulate, acute, pubescent; pedicels 3–6 lin. long, pubescent with spreading hairs. Sepals 2–2 1/4 lin. long, 2/3– 3/4 lin. broad, oblong-lanceolate, acute, pubescent like the pedicels. Corolla 10–12 lin. long, covered outside with a short spreading pubescence, glabrous in all parts within; tube 6–7 lin. long, 1 3/4 lin. in diam. at the inflated base, above which it is slightly curved and cylindric, shortly funnel-shaped and about 2 lin. in diam. at the mouth, blackish-purple within, except at the apex and base; lobes 4–5 lin. long, greenish-black within, ovate in the basal part, linear above, replicate, erect, connate at the apex, gibbous-carinate within near the base, where, at the sinuses, they are externally produced downwards into five spur-like projections 1 1/2–1 3/4 lin. long. Outer corona 1 1/3–1 1/2 lin. long, cup-shaped at the base, with 5 erect oblong lobes 3/4 lin. long, bifid to half-way down, the segments linear and divergent-curved at their tips; inner coronal-lobes 1 lin. long, erect, linear, arising just within the sinuses between the lobes of the outer corona and neither incumbent on, nor inflexed over the anthers. Staminal-column 1/2– 2/3 lin. long; filaments of the stamens very shortly free above their attachment to the dilated top of the style; anthers small, oblong, inflexed over the convex top of the style.